Scallops are edible bivalves similar to oysters and clams. The type of scallop found in Tampa bay is known as the Bay Scallop. Because they require clear water and healthy seagrass beds to thrive, they are a great indicator of the health of the bay.
Most scallops are free swimming and move through the water by opening their shells and clapping them shut, squeezing jets of water from the shells. As a result, the muscle that controls the 'hinge' of the shell is much larger than that of oysters or clams.
Bay scallops may reach a shell height of two inches and generally live only one year. Shells have 17-18 ribs that are squarish and may be white, gray-brown, yellow or orange in color. The scallop has a row of striking blue eyes along the outer lip of its shell, the better to watch out for the many predators - including people - who like to dine on its tasty muscle.
One of the cool features of the scallop is its ability to filter water. It filter feeds continuously on bits of organic material from the water, helping to keep the water clean. It does this by funneling water over open pathways called gills. One of these pathways takes in water and skims off particles, while another expels the filtered water along with digestive wastes.
Bay scallops once were plentiful in Tampa Bay, and even supported a commercial harvest. But overfishing, combined with pollution, virtually eliminated the scallop from Tampa Bay by the 1970s. Scientists now are working to bring back scallop populations, since water quality has improved enough to support viable scallop stocks again. But, because scallops only live one year, and everything likes to eat them, producing a sustainable population may take many decades.
Every summer, Tampa Bay Watch and the Tampa Bay Estuary Program sponsor the "Great Bay Scallop Search." During this event, volunteers snorkel along the seagrass flats in lower Tampa Bay and search for scallops. According to Chris Sutton of Tampa Bay Watch, 2007 was a banner year, with 555 scallops found - a new record!
For researchers like Dr. Bill Arnold of the Florida Fish and Wildlife Conservation Commission, the good news offers additional evidence that Tampa Bay is indeed getting better and may one day harbor a sustainable scallop population again.
"It is really important to improve the quality of the water," Dr. Arnold said, "as the seagrasses depend on clean water, and the scallops depend on the grasses."